The present invention relates to a method for conserving water in maintenance of planted expanses of grass or other ground covers, such as ivy, pachysandra, myrtle, and the like, referred to herein as "lawns" regardless of the nature of the planting. The present invention is applicable in any situation where the ground has little or no water holding capacity, as is the case, for example, of sand or shale. The invention is particularly applicable for new construction and where the lawn is provided by laying a sod of grass or other ground cover. In such situations, water that penetrates the planted layer rapidly percolates downward through the ground below where the roots of the grass or other ground cover can reach it. This necessitates frequent and sometimes daily watering for the life of the lawn. In order to overcome this disadvantage, the present invention provides a ne method for conserving water under the planted layer to aid in lawn maintenance.